Kositanont Uraiwan, Naigowit Pimjai, Imvithaya Amporn, Singchai Chantra, Puthavathana Pilaipan
Department of Microbiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
J Med Assoc Thai. 2003 Feb;86(2):136-42.
To investigate the prevalence of antibodies to Leptospira serovars in rodents and shrews trapped in urban and rural areas in low and high endemic areas in Thailand.
A total of 1,664 serum samples were collected from rodents and shrews in areas of low and high endemicity for leptospirosis. Four areas classified by case rates (CR) per 100,000 population of leptospirosis were urban Area I Bangkok (CR = 0.07), rural Area II (CR = 0.24), rural Area III (CR = 1.97) and rural Area IV (CR = 48.20). All serum samples were investigated for antibodies to leptospires by microscopic agglutination test (MAT) using antigens from each of the 22 pathogenic serovars of Leptospira interrrogans: australis, autumnalis, ballum, bangkok, bataviae, bratislava, canicola, celledoni, copenhageni, djasiman, grippotyphosa, hardjo, hebdomadis, icterohaemorrhagiae, javanica, pomona, pyrogenes, rachmati, saigon, sejroe, tarassovi and wolffi and one non-pathogenic strain of L. biflexa serovar patoc.
Ninety-four (5.6%) serum samples were positive for Leptospira antibodies. The most commonly detected antibodies were to serovars pyrogenes (39.1%), sejroe (19.1%), bataviae (10.0%), pomona (6.4%), autumnalis (5.5%), copenhageni (3.6%) and javanica (3.6%). The positive rates in Area I, II, III and IV were 7.6 per cent, 2.9 per cent, 4.6 per cent and 7.1 per cent, respectively. The seroprevalence in rural areas tended to increase significantly with high endemicity for leptospirosis (Chi-square for trend, p = 0.04). The seropositive rates by animal species were 39/496 (7.9%), 22/322 (6.8%), 23/492 (4.7%), 6/170 (3.5%), 4/175 (2.3%), 0/4 (0%) and 0/5 (0%) in Rattus norvegicus, Rattus exulans, Rattus rattus, Bandicota indica, Bandicota savilei, Mus musculus and Suncus murinus, respectively. There was a statistical trend between seropositive rates in R. exulans and endemicity for leptospirosis (Chi-square for trend, p = 0.04).
The 5.6 per cent of rodents and shrews trapped in urban and rural areas in Thailand were reservoirs of leptospires. The results of high seroprevalence in rats also indicate the high endemicity for leptospirosis.
调查在泰国低流行区和高流行区城乡捕获的啮齿动物和鼩鼱中钩端螺旋体血清型抗体的流行情况。
从钩端螺旋体病低流行区和高流行区的啮齿动物和鼩鼱中总共采集了1664份血清样本。根据每10万人口中钩端螺旋体病的发病率（CR）将四个地区分类为：城市地区I曼谷（CR = 0.07）、农村地区II（CR = 0.24）、农村地区III（CR = 1.97）和农村地区IV（CR = 48.20）。所有血清样本均通过显微镜凝集试验（MAT），使用问号钩端螺旋体的22种致病性血清型中的每种抗原进行钩端螺旋体抗体检测：澳洲型、秋季型、拜伦型、曼谷型、巴达维亚型、布拉迪斯拉发型、犬型、塞氏型、哥本哈根型、爪哇型、流感伤寒型、哈焦型、七日热型、出血黄疸型、爪哇型、波摩那型、致热型、拉赫马蒂型、西贡型、双曲钩端螺旋体型、塔拉索夫型和沃尔夫型以及双曲钩端螺旋体血清型帕托克的一种非致病性菌株。
94份（5.6%）血清样本钩端螺旋体抗体呈阳性。最常检测到的抗体针对的血清型为致热型（39.1%）、双曲钩端螺旋体型（19.1%）、巴达维亚型（10.0%）、波摩那型（6.4%）、秋季型（5.5%）、哥本哈根型（3.6%）和爪哇型（3.6%）。地区I、II、III和IV的阳性率分别为7.6%、2.9%、4.6%和7.1%。钩端螺旋体病高流行区农村地区的血清阳性率有显著上升趋势（趋势性卡方检验，p = 0.04）。按动物种类划分的血清阳性率在挪威大鼠中为39/496（7.9%）、黑家鼠中为22/322（6.8%）、褐家鼠中为23/492（4.7%）、板齿鼠中为6/170（3.5%）、萨氏板齿鼠中为4/175（2.3%）、小家鼠中为0/4（0%）、臭鼩中为0/5（0%）。黑家鼠的血清阳性率与钩端螺旋体病的流行程度之间存在统计学趋势（趋势性卡方检验，p = 0.04）。
在泰国城乡捕获的啮齿动物和鼩鼱中有5.6%是钩端螺旋体的宿主。大鼠中血清阳性率高的结果也表明钩端螺旋体病的高流行率。
